Apparatus for salvaging vapor gas from hydrocarbon liquids



March 22, 1960 CARROLL, 5 ET AL 2,929,463

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March 22, 1960 CARRQLL, 5 ET AL 2,929,463

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I50 I I64 0 0 0 a a 2 l w w m w mmvrozes Q BY APPARATUS FOR SALVAGING VAPQR GAS FRGM HYDROCARBQN LiQUiDS Application July 23, 1954, Serial No. 445,348

3 Claims. (Cl. 183-25) This invention relates to an apparatus for salvaging vapor gas from hydrocarbon liquids, and particularly to a device for continuously treating a flowing stream of hydrocarbon liquid fuel securing therefrom a vapor gas of substantially constant B.t.u. value as well as providing a liquid fuel with a substantially constant B.t.u. value.

In the manufacture of hydrocarbon fuels from petroleum, coal or the like, it is found that the various hydrocarbon liquid fuels, such as gasoline, benzine, benzol and the like, contain therein slivers of high volatile mate rials, such as butane, pentane and the, like, which are substantially entrapped and carried by the liquid material.

These slivers of highly volatile materials readily vaporize upon contact with the atmosphere so that the agitation of the liquid during handling constantly brings a few of these slivers into contact with the atmosphere so that the handling, expansion or the like causes a constant evolution or loss of such fuels.

All users of hydrocarbon fuels, such as gasoline or the like, are well aware of the heavy fumes of hydrocarbon material which are liberated during the handling of the fuels. The ordinary user of gasoline, or other such hydrocarbon fuels, becomes so accustomed to the escape or loss of portions of his fuel into the atmosphere that little attention is paid thereto. However, it is apparent that valuable constituents of the hydrocarbon fuel are material from the hydrocarbon being lost by vaporization and dissipation to the atmosphere (the Government allows 2% loss for tax purposes), and not only are the fuel values being lost, but the presence of the highly volatile and frequently highly explosive vapors produces a fire and explosion hazard in the handling of such hydrocarbon fuels.

One of the annoying features of the high volatile materials in usual hydrocarbon fuels is so-called vapor lock. The high volatile material in the fuel being constantly under a tendency to vaporize, will vaporize under various undesirable conditions. For example, in a fuel pump, where suction is applied to the liquid fuel, the reduction in pressure may give the high volatile materials a chance to vaporize, in which case, they will occupy a much larger volume than while in the liquid phase, and only extreme pressures and low temperatures can cause these high volatiles to again condense to a liquid. Accumulation of these high volatile materials as a vapor may cause a break in the fuel column so that the pump will become inoperative to elevate the fuel from a tank to a discharge system. Further, should any portion of the liquid fuel system become slightly heated, the increase in temperature therein may produce volatilization of the high volatiles so that a fuel line may be blocked because of a quantity of vapor therein.

The tendency of these slivers of high volatile material to produce vapor lo'ck has been extremely annoying in theaviation industry which has found it necessary to utilize high pressure fuel pumps with the fuel constantly under pressure to reduce the tendency to vapor lock. Further, it has been found necessary "to introduce de- 2,929,463 Patented Mar. 22, less vaporizing devices which constantly operate on the fuel in the aircraft storage system to remove the high volatiles therefrom and to discharge the same into the atmosphere. The presence of the high volatile materials not only produces dangerous operation of the motor system, but the discharge of the high volatiles introduces a fire hazard because of the extremely explosive nature of the high volatile air mixtures resulting.

Various attempts have been made to free these high volatile materials from the entraining liquids, either to stabilize the liquids or to provide the vapors as fuel material. Heretofore, considerable difiiculty has been had in securing and utilizing these vaporous fuels because of the constantvariation of the quality of the fuels produced. For example, it has been found that certain vapors can be produced by taking a quantity of hydrocarbon fuel, such as gasoline, benzine or the like, and containing it in a chamber and passing a stream of air therethrough to produce agitation of the liquid to liberate the slivers of high volatile materials contained therein. However, the gas produced by such method has been highly unsatisfactory in that the first gas produced is extremely rich in B.t.u. values with the quality rapidly decreasing from the beginning to the end of the treatment.

Also, various systems have been attempted utilizing high pressures or high temperatures or both to free the high volatile constituents from the entraining liquid. These processes have not only been found hazardous, but for the same reasons, the fuel produced has been unsatisfactory because of the varying quality thereof.

These high volatiles readily vaporize upon contact with the air or upon release of pressure, so that, when air is bubbled through the liquid, any sliver contacted by an air bubble will vaporize and be carried along by the air bubble, the remaining liquid being substantially freed of the high volatiles and may be handled without evolving excessive quantities of dangerous vapor.

The present invention relates to a system for treating hydrocarbon liquid fuels,"such as gasoline and the like, to not only stabilize the liquid fuel by eliminating the high volatiles which heretofore have been evolved in random manner so that there was a constant fire and explosion hazard about the fuel, but also toutilize the fuel so recovered and to maintain the quality thereof at a substantially constant B.t.u. value so that the utilization thereof will be economical and satisfactory.

In the construction according to the invention, a plurality of generator or vapor evolving cells are provided with means for pumping a continuous stream of fuel from any suitable source thereinto and having the level of fuel in the evolving cell maintained by means of an exhaust pump which exhausts the stabilized liquid therefrom and returns it to suitable storage. Simultaneously, a quantity of air is passed through the cell by means of a diffuser having a plurality of apertures to produce streams of air bubbles upwardly through the containedliquid in the cell with the volume of air and the volume of fuel passing through the cell being regulated to produce a constant ratio of air to treated material so that the evolved vapor will be substantially constant in B.t.u. value.

A plurality of cells may be used so that the liquid fuel may be passed through one cell and treated with one ratio of air and then passed through a separate cell and treated with a separate or different ratio or air to produce two diiferent types of vapor fuels. Each of these vapor fuels will have a substantially constant B.t.u.

' for a single hydrocarbon fuel to completely stabilize the same, it will usually be found that different liquids or different grades of the same liquid or same type of liquid will be passed through the various cells and the resultant hydrocarbon vapors may be utilized independently or together, as may be desired.

In the preferred construction according to the invention, first and second cells are provided together with a first and second supply pump and a first and second return pump, and interconnections provided between the various pumps and cells so that the liquids supplied to either or both cells may be determined at will from either of a plurality of sources and the resultant liquid either commingled or returned to separate tanks, as may be desired. The piping between the pumps and the cells being provided with various valves and cross-connections so that either pump may be operated to supply fuel to either cell from either of two independent sources or the return pump may be utilized to draw fuel from either of the cells and return it to the same or independent storage sources, means being provided so that the interconnections and pumps may be utilized at will.

It is accordingly an object of the invention to provide an improved method of stabilizing the B.t.u. value of hydrocarbon fuels.

It is a further object of the invention to salvage the high volatile components of hydrocarbon fuels. 7

it is a furtherobject of the invention to provide a high volatile liberating system with means for interconnecting the system at will. 7

It is a further object of theinvention to provide an improved high volatile evolving cell.

It is a still further object of the invention to provide an improved control system for a vapor evolving cell.

Other objects and many of the attendant advantages of the present invention will be apparent from the following detailed description taken in connection with the accompanying drawings in which:

Figure 1 is a perspective view of a vapor evolving system with the top portion cut away;

Figure 2 is a perspective view of a simplified modification according to the invention;

Figure 3 is a sectional elevation through a vapor evolving cell according to the invention;

Figure 4 is a top plan view of a refined modification according to the invention;

Figure 5 is a sectional elevation taken substantially on the plane indicated by the section line 55 of Figure 4 and showing the construction of the refined modification;

Figure 6 is a cross-sectional view through the refined modification taken substantially on the plane indicated by the section line 66 of Figure 5;

Figures 7, 8, 9 and 10 are perspective views of the top connection of the fuel stabilizer and the fuel salvage system according to the invention showing the different arrangements to secure the various flow paths therethrough;

Figures 11 to 82, inclusive, show the various valve settings to secure the various possible flow paths through the device, the various valves being arranged in the position and setting according to the flow path to be established in the various networks as illustrated in Figure I;

Figure 83 illustrates the flow connections to the refined modification as indicated in Figures 4, 5 and 6.

In the construction of the device according to Figure 1, a first treating cell 10 and a second treating cell 12 are connected by means of suitable networks presently to be described to a first supply pump 14 and a second supply pump 16, and'liquid fuel is exhausted from the cells by means of a first return pump 18 and a second return pump 20.

Each of the cells 10 and 12, as most clearly seen in Figure 3, is constructed as having a tubular body portion 22 having a bottom closure 24 which is preferably a supporting platform for the cells. A top 26 is secured intake manifold 74 between 4 in fluid-tight relation to the body 22 and the bottom 24 is provided with an aperture 28 in which is screwed a drain pipe 30. The body 22 is provided with an aperture 32 intermediate the ends thereof and a supply conduit 34 is threadedly connected therein.' Likewise, the body 22 is provided with a return aperture 36 into which is threadedly connected a return conduit 38. The return conduit 38 is preferably in the form of an L having a downturned goose-neck portion 40 extending into the body 22 and directed toward the bottom thereof. It is to be understood that various lengths of goose-neck 40 may be arranged to determine the depth of liquid fuel maintained within the body 22.

A diffuser head 42 is mounted in the bottom of the body 22 and preferably is provided with a rim 44 and a perforated top portion 46 having apertures 48 therein, while an air duct 50 is rigidly connected to the diffuser head 42 and preferably sealed in fluid-tight relation thereto. The area of the apertures 48 in the diffuser head 46 is preferably substantially 65% of the area of the bore 52 of the air duct 50. The top 26 is provided with an aperture 54 through which the air duct 50 extends and an upstanding collar 56 about the aperture 54 is threaded to receive the packing nut 58 to compress a packing gland 60 into fluid-tight relation with the side of the duct 50.

The top 26 is also provided with an aperture 62 through which extends a vapor passage 64 with the aperture 62 being surrounded by a collar 66 to receive a packing nut 68 to compress a packing 70 into sealing relation with the vapor passage 64. Top 26 may be secured to the body in any suitable way, herein shown as stud bolts 72 extending through the top 26 and screwed into the metal of the body 22.

.Ihe air ducts 58 of the first and second cells 10 and 12 are connected together by means of an air intake manifold 74 and the vapor passages 64 of the first and second cells It) and 12 are connected together by means of an output manifold 76. Preferably, one of the manifolds 74 or 76 is offset by means of nipples '78 and 80 to provide a working space between the manifolds 74 and 76. An interconnecting duct 82 is provided between the manifolds 74 and 76 intermediate the ends thereof and provided with a control valve 81. The interconnecting duct 82 may be in offset formation as shown in Figure 2, or where space is not at too much of a premium, may be straight, as shown in Figures 7 to 10, inclusive.

An air intake duct 86 is connected to air intake manifold 74 between the junction of the cross-interconnect 82 and the air duct 50 of the second cell 12. A valve 88 is connected in the air intake manifold 74 between the junction of the interconnecting duct 82 and the air supply duct 86. Likewise, a valve 90 is placed in the air the air supply duct 86 and the air duct 50 of the second cell 12.

A fuel output duct 92 is connected to the output manifold 76 intermediate the ends thereof. A valve 94 is placed between the vapor passage 64 of the first cell 10 and the output duct 92. Likewise, a valve 96 is interposed in the output duct 76 between the interconnecting duct 82 andthe output duct 92.

Each of the valves 81, 88, 90, 94 and 96 is provided with an indicator handle 98 which, when turned transversely to the duct on which it is mounted, indicates that the valve is closed, and when it is extending longitudinally with the duct, indicates that the valve is open.

The manifolds 74. and 76 together with the interconnecting duct 82 and the air supply duct 86 and the output duct 92 together with the valves therein may be set up to provide a plurality of flow paths therein. For example, in Figure 7, with the 'valve 84 in the interconnecting duct82 closed and the remaining valves open, the air will flow into each of the cells 10 and 12 through each of the air intakes 50 and the output vapor will flow through the vapor passages 64 and outwardly through the fuel duct 92.

Likewise, in Figure 8, with the valves 88 and 96' closed, the air will flow downwardly through the air intakeduct 50 of the second cell 12 and outward through the manifold 76 to be blocked by the valve 96 and then across the interconnect 82 and downward into the air intake duct 50 of the first cell and outwardly through the vapor passage 64 and through the valve 94 to the fuel duct 92. In this connection, it will be seen that the air flows in series through the generator cells so that the vapor having a given ,B.t.u. value is resaturated in one Of the cells to secure a maximum carriage or" fuel vapor and a different B.t.u. value.

In a valve set-up according to Figure 9, valves 88,

84 and 94 are closed so that the first cell 10 is completely cut off and vapor will only flow from the second cell 12. Likewise, in the modification of Figure 10, the second cell 12 is cut off and vapor will only flow from the first cell 10.

The fuel supply system comprises a supply pipe network having a first supply pipe 100 and a second supply pipe 102, a supply intake pipe 104 connected to the supply pipe 109 and to the intake port of the first supply pump 14 and the second supply intake pipe 10% connected to the intake port 110 of the second supply pump 16. A first supply pipe interconnect 112 is connected to the first supply pipe 100 by means of a T-connection 114 and may be connected at will to the intake pipe 168 by means of the valve C. A second supply pipe interconnect 116 is connected to the second supply pipe 102 by means of a T-connection 118 and a connection to the supply pipe 194 is controlled by means of the valve D. It will be apparent that the valves C or D may be opened or closed at will to provide suitable flow paths for the supply of fuel from any suitable storage tanks, not shown, to either or both of the supply pumps 14 and 16.

The output port 122 of the first supply pump 14 is connected to the supply conduit 34 of the first cell 10 by means of a supply tube 124. -Afiow regulating valve 126 'is supplied in the fluid supply conduit 34 to control the rate of fluid flow therethrough. Each of the pumps 14, 16, 18 and 20 is provided with an internal relief passage so that excessive pressures cannot be built up in the pumps or the tubes connected thereto.

. The second supply'pump' 16 has the output port 128 connected. to the supply, conduit 34 of the second cell 12 by means of a supply tube 130. A first cross-supply tube 132 is connected to the supply tube 124 by means of 'a three-way four-position valve A and connects to the supply tube 134 by means of a T 134. Likewise, a second cross-supply tube 136 is connected to the tube 131) by means of a three-way four-position valve B and connects to the tube 124 by means of the T-connection 138. It being apparent that by means of the valves A and B, the pumps may be connected directly to either of the cells 10 or 12 while either one of the pumps 14 or 16 may be connected to both cells, as may be desired.

Each of the return conduits 38 is providedwith a throttle valve 140 to control the level of the liquid fuel within the cells 10 or 12, and a return network of tubes is connected to the return conduits 38 and to an input port 142 of the first return pump 18 and an input port 144 of the second return pump 26. The network comprises a first return tube 146 which connects the return conduit 38 of the first cell to the intake port 142 of the first return pump'18. And likewise, a second return tube 148 which connects the output conduit 38 of the second cell 12 to the input port 144 of the second return pump 20.

A first cross-return tube 150 is connected to the return tube 146 by means of the three-way four-position valve G and connected to the return tube 148 by means of the T-connection 152i, Likewise, a second return cross-return tube 154 is connected to the return tube 148 by means of a three-way four-position valve H and is connected to the return tube 146 by means of the T-connection 156. By this, it will be apparent that the return tubes may connect either or both of the first and second cells 10 and 12 to either or both of the return pumps 18 or 20 so that either pump 18 or 20 may pump from either cell or from both cells, or both pumps may pump from one cell or both cells, as the condition may require.

The discharge pipe network comprises a first discharge pipe 160 and a second discharge pipe 162 with a discharge pipe 164 extending from the output port 166 of the first output pump 18 and connecting to the discharge pipe 160 by means of the two-way angle valve F. Likewise, the output port 168 of the second output pump 20 is connected to the pipe 162 by a discharge pipe 170. The connection being made by the two-way angle valve E. It being apparent that either of the pumps 18 or 20."

may be connected to either or both of 16th or 162, as'may be desired.

A first cross-discharge pipe 180 is connected to the discharge pipe 160 by means of a T 182 and flow from discharge pipe 170 is controlled by means of the angle valve E. A second cross-discharge pipe 184 is connected to the discharge pipe 162 by means of a T 186 and flow from pipe 164 is controlled by the two-way three-position valve F.

When both of the pumps 14 and 18 are out of use, a first clutch 174 may be disconnected to prevent the running of the pumps 14 and 18 and the consequent the discharge pipes wear thereon. Likewise, if the pumps 16- and 20 are inoperative, the second clutch 176 may be disconnected to disconnect the pumps 16 and 20 from a driving motor 178. In the operation of the device according to the initial embodiment thereof, the supply pipes and 102 will be connected to any suitable source of' supply, preferably a different source. Likewise, the discharge pipes and 162 will communicate with any suitable receiver which may be the same or different, as may be desired.

In the operation of the preferred commercial embodiment of the invention according tov Figure 1, various valves A, B, C, D, E, F, G and H maybe arranged to block the various pipes or to open the various cross-pipes in the networks so that a plurality of flow paths may be established to determine the particular operation of the device. For simplicity of illustration and description, the valves A, B, G and H have been indicated as T-valves or three-way four-position valves, while the valves C, D, E and F have been indicated as angle valves or threeposition two-way valves. Obviously, these single valves could be replaced by normal valves of various kinds installed in the tubes themselves instead of being connected in the three-way position.

The various valve settings to determine the various fiow paths and the flow paths established thereby are set forth in the following tabulation of the valve settings:

Flow path 1-Figure 11 Liquid fuel supply pipe 102 through second supply pump'16 to both cells; return from both cells to second return pump 20 and discharge through second discharge pipe 162 Flow path 2Figure I2 Liquid fuel from supply pipe 102 through secondsupply pump 16 to second cell 12;v retutnlfitom belt-12 th 

